HTTP 400和500错误信息

当我运行我的应用程序，我有一个HTTP错误：HTTP 400和500错误信息

HTTP Status 404 - /ProjectName/

这是我的项目的URL：

localhost:8080/Initiation1/

当我键入此字符串到地址栏：

localhost:8080/Initiation1/CarteIdentite

，我在此HTTP 500错误消息：

javax.servlet.ServletException: Error instantiating servlet class ca.web.CarteIdentite 
    org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:472) 
    org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:100) 
    org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:929) 
    org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:405) 
    org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:269) 
    org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:515) 
    org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:300) 
    java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source) 
    java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source) 
    java.lang.Thread.run(Unknown Source) 


root cause 

java.lang.ClassNotFoundException: ca.web.CarteIdentite 
    org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1678) 
    org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1523) 
    org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:472) 
    org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:100) 
    org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:929) 
    org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:405) 
    org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:269) 
    org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:515) 
    org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:300) 
    java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source) 
    java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source) 
    java.lang.Thread.run(Unknown Source)

这是我的servlet代码：

package ca.web; 

import java.io.IOException; 
import javax.servlet.ServletException; 
import javax.servlet.annotation.WebServlet; 
import javax.servlet.http.HttpServlet; 
import javax.servlet.http.HttpServletRequest; 
import javax.servlet.http.HttpServletResponse; 
import java.io.IOException; 
import java.io.PrintWriter; 
import javax.servlet.ServletConfig; 

/** 
* Servlet implementation class CarteIdentite 
*/ 
@WebServlet("/CarteIdentite") 
public class CarteIdentite extends HttpServlet 
{ 
    // paramètres d’instance 
    private String defaultNom = null; 
    private String defaultAge = null; 
    private String defaultCourriel = null; 
    //init 
    public void init() 
    { 
    // on récupère les paramètres d’initialisation de la servlet 
    ServletConfig config = getServletConfig(); 
    defaultNom = config.getInitParameter("defaultNom"); 
     if(defaultNom==null) 
     { 
      defaultNom="XXXXXXXXXXXXXXXX"; 
     } 
     defaultAge = config.getInitParameter("defaultAge"); 
     if(defaultAge==null) 
     { 
      defaultAge="AAA"; 
     } 
     defaultCourriel = config.getInitParameter("defaultCourriel"); 
     if(defaultCourriel==null) 
     { 
      defaultCourriel="[email protected]"; 
     } 
    } 
    //GET 
    public void doGet(HttpServletRequest request, HttpServletResponse response) throws 
    IOException, ServletException 
    { 
    // on récupère les paramètres du formulaire 

    String nom = request.getParameter("txtNom"); 
    if (nom == null) 
    { 
     nom = defaultNom; 
    } 
    String age = request.getParameter("txtAge"); 
    if (age == null) 
    { 
     age = defaultAge; 
    } 
    String courriel = request.getParameter("txtCourriel"); 
    if (courriel == null) 
    { 
     courriel = defaultCourriel; 
    } 
    // on affiche le formulaire 
    response.setContentType("text/html"); 
    PrintWriter out=response.getWriter(); 
    out.println 
    (
     "<html>"+ 
     "<head>"+ 
     "<title>Carte d’identité</title>"+ 
     "</head>"+ 
     "<body>"+ 
     "<center>"+ 
     "<h2>Carte d’identité</h2>"+ 
     "<form action=’’ method=’post’>"+ 
     "<table>"+ 
     "<tr>"+ 
     "<td>Nom:</td>"+ 
     "<td><input name=’txtNom’ value=’"+nom+"’ type=’text’ size=’30’></td>"+ 
     "</tr>"+ 
     "<tr>"+ 
     "<td>Age:</td>"+ 
     "<td><input name=’txtAge’ value=’"+ age +"’ type=’text’ size=’3’></td>"+ 
     "</tr>"+ 
     "<tr>"+ 
     "<td>Courriel:</td>"+ 
     "<td><input name=’txtCourriel’ value=’"+courriel+"’ type=’text’ size=’30’></td>"+ 
     "</tr>"+ 
     "</table>"+ 
     "<table>"+ 
     "<tr>"+ 
     "<td><input type=’submit’ value=’Envoyer’></td>"+ 
     "<td><input type=’reset’ value=’Effacer’></td>"+ 
     "</tr>"+ 
     "</table>"+ 
     "</form>"+ 
     "</center>"+ 
     "</body>"+ 
     "</html>"  
    ); 
    } 
    /** 
    * @param request la requête HTTP du client 
    * @param response la réponse HTTP qu’on va construire 
    */ 
    public void doPost(HttpServletRequest request, HttpServletResponse response) throws IOException, ServletException 
    { 
    //on passe la main au GET 
    doGet(request, response); 
    } 
}

这是我的web.xml文件：

<?xml version="1.0" encoding="UTF-8"?> 
<!DOCTYPE web-app SYSTEM "http://java.sun.com/dtd/web-app_2_3.dtd"> 
<web-app> 
    <servlet> 
     <servlet-name>CarteIdentite</servlet-name> 
     <servlet-class>ca.web.CarteIdentite</servlet-class> 
      <init-param> 
      <param-name>defaultNom</param-name> 
      <param-value>inconnu</param-value> 
      </init-param> 
      <init-param> 
      <param-name>defaultAge</param-name> 
      <param-value>XXX</param-value> 
      </init-param> 
      <init-param> 
      <param-name>defaultCourriel</param-name> 
      <param-value>inconnu</param-value> 
      </init-param> 
     </servlet> 
     <servlet-mapping> 
     <servlet-name>CarteIdentite</servlet-name> 
     <url-pattern>/CarteIdentite</url-pattern> 
    </servlet-mapping> 
</web-app>

这里是我的项目结构：

project structure